# -*- coding:utf-8 -*-


# Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties:
#
#
#
# Integers in each row are sorted in ascending from left to right.
# Integers in each column are sorted in ascending from top to bottom.
#
#
#
#
# For example,
#
# Consider the following matrix:
#
#
# [
#   [1,   4,  7, 11, 15],
#   [2,   5,  8, 12, 19],
#   [3,   6,  9, 16, 22],
#   [10, 13, 14, 17, 24],
#   [18, 21, 23, 26, 30]
# ]
#
#
# Given target = 5, return true.
# Given target = 20, return false.


class Solution(object):
    def searchMatrix(self, matrix, target):
        """
        :type matrix: List[List[int]]
        :type target: int
        :rtype: bool
        """
        if not matrix:
            return False
        m, n = len(matrix), len(matrix[0])
        r , c = 0, n-1
        while r < m and c >= 0:
            if matrix[r][c] == target:
                return True
            if matrix[r][c] > target:
                c -= 1
            else: 
                r += 1
        return False
